We have listed some of the most common error codes for Samsung ACs:

Here is the updated table with the information about the additional error codes you provided:

Error code	Description	Possible Causes and Solutions
E101, E102	Communication Error (Interior Exterior)	– Check the communication cable connections.
		– Make sure there is no electromagnetic interference nearby.
		– Check the condition of the cables and replace them if necessary.
E121	Room Temperature Sensor Error	– Check sensor location and replace if necessary.
E122	Internal Pipe Temperature Sensor Error	– Inspect and replace temperature sensors in the internal piping.
E154	Fan Error (Indoor)	– Check the status of the fan and its connection.
		– Replace the fan if necessary.
E162	EEPROM error (Indoor)	– Consult a technician to replace or reprogram the EEPROM.
E163	Option Error	– Check the system configuration and make corrections according to the user manual.
E203	Communication Time Out (Main Micom and Investor Micom)	– Check connections and replace faulty components if necessary.
E221	Outdoor Temperature Sensor Error (OUT-TH – Outdoor Temperature)	– Check connections and replace sensor if necessary.
E231	Condenser Temperature Sensor Error (CON-TH – Cond Temperature)	– Inspect and replace the affected sensor.
E251	Discharge Temperature Sensor Error (DIS-TH – Discharge Temperature)	– Check connections and replace sensor if necessary.
E416	Discharge Temperature Sensor Overheating	– Check air circulation and make sure the system is working properly.
E422	EEV or Valve Closing Error – Self-Diagnosis	– Inspect the valve and its connections. Replace valve if necessary.
E440	Prohibited Condition Error (Heating)	– Check the configuration and operating conditions in heating mode. Adjust as necessary.
E441	Prohibited Condition Error (Cooling)	– Check the configuration and operating conditions in cooling mode. Adjust as necessary.
E458	Fan Error (Outdoor)	– Check the status of the fan in the outdoor unit and its connection.
E461	Compressor Start Error	– Check compressor starting system and make necessary repairs.
E462	AC Input Current Limit Error	– Check the AC input current limit and make adjustments as necessary.
E464	IPM Overcurrent Error (OC)	– Inspect the IPM power module and replace if necessary.
E465	Compressor Voltage/Current Limit Error	– Check compressor voltage/current limit and make adjustments if necessary.
E466	DC-Link Low/High Voltage Error	– Check the DC-Link voltage and make adjustments as necessary.
E467	Compressor Cable Missing Error	– Check compressor cable connections and repair if necessary.
E468	Current Sensor Error	– Inspect current sensor and replace if necessary.
E469	DC-Link Voltage Sensor Error	– Check DC-Link voltage sensor and replace if necessary.
E470	EEPROM Data Error (no data)	– Check the presence of data in the EEPROM and replace if necessary.
E471	EEPROM Data Error (Main Micom and Micom Inverter)	– Check the data in the EEPROM of the main Micom and Micom inverter. Replace the EEPROM if necessary.
E474	Heat Sink Sensor Error	– Inspect the heat sink sensor and replace if necessary.
E483	Overvoltage Protection Error	– Check voltage conditions and make adjustments as necessary.
E484	PFC Overload Error	– Review the PFC loading conditions and make adjustments if necessary.
E485	Input Current Sensor Error	– Inspect the input current sensor and replace if necessary.
E488	AC Input Voltage Sensor Error	– Check the AC input voltage sensor and replace if necessary.
E500	Heat Sink Overheating Error	– Check airflow to the heat sink and make adjustments as necessary.
E554	Gas Leak Error	– Inspect the system for refrigerant gas leaks and repair as necessary.

Error code	Meaning	probable cause	Troubleshooting
CL	Auto Clean Indicator	Indoor unit that produces odors	Run the “Auto-Clean” command to remove the odor.
CF	Filter Clean/Reset Reminder	Dirty filter	Clean/replace dirty filter on your indoor unit
D.F.	Automatic defrosting	The air conditioning is defrosting	Wait for the automatic defrost to finish.
E3	Indoor fan motor malfunction	Defective indoor fan or circuit board	Replace the indoor fan or circuit board, depending on which is defective
E4	Forced defrosting	Low coolant level, faulty pump, broken temperature sensor or pressure fluctuation	Contact the nearest Samsung service center
E5	Indoor heat exchanger sensor open/short	Defective outdoor heat exchanger sensor	Replace the indoor heat exchanger sensor
E6	Outdoor heat exchanger sensor open/short	Defective outdoor heat exchanger sensor	Replace heater temperature sensor
E7	Heater temperature sensor open/short circuit	Defective heater temperature sensor	Replace heater temperature sensor
C2	Inner pipe sensor failure	Defective inner pipe sensor	Replace the inner pipe sensor
E101	Communication failed (indoor unit)	Faulty power cables or connections around the indoor unit	Check for loose connections or power cables and fix them.
E102	Communication failed (outdoor unit)	Faulty power cables or connections around the outdoor unit	Check for loose connections or power cables and fix them.
HE	Electric heater overheated	Power Overload	Replace Heater Temperature Sensor or PCB
E201	Communication failed (between indoor and outdoor units)	Loose connections or defective PCB (printed circuit board)	Check for loose connections outdoors and indoors and if not, replace the main PCB
E1/21	Room temperature sensor failure	Faulty room temperature sensor	Contact the nearest Samsung service center
E1/22	Heat exchange temperature sensor failure	Malfunctioning heat exchanger temperature sensor	Contact the nearest Samsung service center
E1/54	Faulty condenser or fan motor	–	Replace the condenser or fan motor.
E1/63	defective EEPROM	–	Replace the EEPROM

Error codes for Multi System AC Samsung:

Here is the updated table with the information on error codes for Multi System AC in indoor units and verification methods:

Error code	Description	Possible Causes and Solutions
E1-01	Communication Error (inability to receive data)	– Check the connection of the communication cable.
		– Check the cable connection in other indoor units or indoor PCB.
E1-02	Communication Error (outdoor unit cannot communicate)	– Check the cable connection on another indoor unit or on the indoor PCB.
E1-21	Room Temperature Sensor Error	– Check the room temperature sensor and connection on the indoor PCB.
E1-22	Heat Exchanger Temperature Sensor Error (inside)	– Check the heat exchanger sensor inside and the connection on the inside PCB.
E1-23	Heat Exchanger Temperature Sensor Error (outside inside)	– Check the heat exchanger sensor outside the interior and the connection on the interior PCB.
E1-28	Heat Exchanger Temperature Sensor (inside) detached error	– Check the heat exchanger sensor inside.
E1-29	Heat Exchanger Temperature Sensor (outside inside) detached error	– Check the heat exchanger sensor outside the interior.
E1-30	Heat Exchanger Temperature Sensor (inside and outside) detached error	– Check the heat exchanger sensors inside and outside the inside.
E1-54	Fan Motor Malfunction (inside)	– Check the fan motor and wiring in the indoor unit.
E1-61	More than 2 indoor units in cooling and heating mode simultaneously	– Check the operation mode of other indoor units.
E1-62	EEPROM error (inside)	– Consult a technician to replace or reprogram the EEPROM in the indoor unit.
E1-63	Option code configuration error	– Check and adjust the option code as necessary.
E1-85	Incorrect wiring	– Check the cable connections between the indoor and outdoor unit.
E2-01	Incorrect number of paired indoor units	– Check the cable connections between another indoor unit and the outdoor unit.
E2-51	Compressor Discharge Sensor Error (Short/Open Circuit)	– Check the compressor discharge sensor on the outdoor unit.
E5-59	Outdoor unit error	– Consult a technician for diagnosis and repair of the outdoor unit.

Error codes for VRF Samsung:

Here is the updated table with information on error codes for VRF (DVM S) in indoor units and related communication and configuration aspects:

Error code	Description	Possible Causes and Solutions
E-101	Communication Error in the Indoor Unit	– Check the connection of the indoor unit and make sure it receives data from the outdoor unit.
E-102	Communication Error between Indoor and Outdoor Unit	– Check the communication between the indoor and outdoor unit. This code is displayed on the indoor unit.
E-108	Error due to repeated address setting	– Check and adjust the address settings as necessary.
E-121	Interior Temperature Sensor Error	– Check the indoor temperature sensor and connection on the indoor unit.
E-122	Indoor Unit EVA IN Sensor Error	– Check the EVA IN sensor of the indoor unit and the connection.
E-123	Indoor Unit EVA OUT Sensor Error	– Check the EVA OUT sensor of the indoor unit and the connection.
E-128	The EVA IN temperature sensor of the indoor unit has detached from the EVA IN tube	– Check the EVA IN temperature sensor and reattach it to the EVA IN tube.
E-129	The EVA OUT temperature sensor of the indoor unit has detached from the EVA OUT tube	– Check the EVA OUT temperature sensor and reattach it to the EVA OUT tube.
E-130	Indoor unit heat exchanger inlet/outlet sensors are detached	– Check the heat exchanger inlet/outlet sensors and reseat them.
E-135	Indoor unit cleaning fan RPM feedback error	– Check the operation of the cleaning fan and its connection.
E-149	Error due to indoor unit AHU master sensor setting	– Check and adjust the AHU master sensor settings as necessary.
E-151	Error due to open EEV of indoor unit (detection 2)	– Check the condition of the EEV valve and repair if necessary.
E-152	Error due to closed EEV of indoor unit (detection 2)	– Check the condition of the EEV valve and repair if necessary.
E-153	Indoor unit float switch error (detection 2)	– Check the float switch and its connection, repair if necessary.
E-154	Indoor unit RPM feedback error	– Check the operation of the indoor unit fan and its connection.
E-161	Indoor unit mixed operation mode error; when the outdoor unit is preparing to operate in cooling	– Check the operation mode of the outdoor unit and make adjustments if necessary.
E-162	MICOM EEPROM error on indoor unit	– Consult a technician to replace or reprogram the EEPROM in the indoor unit.
E-163	Indoor unit remote control option is incorrect or absent	– Check the remote control option settings and correct them as necessary.
E-180	Simultaneous opening of cooling and heating MCU solenoid (detection 1)	– Check the MCU solenoid and its connections.
E-181	Simultaneous opening of cooling and heating MCU solenoid (detection 2)	– Check the MCU solenoid and its connections.

Flashing lights on Samsung air conditioners:

Here is the updated table with information about the flashing lights on Samsung air conditioners and their meanings:

Light Sequence	Description	Possible Causes and Solutions
Off – Flashing – Off	Room Temperature Sensor Error (open/short circuit)	– Check the room temperature sensor and its connection.
Flash – Flash – Off	Heat Exchanger Temperature Sensor Error (open/short circuit)	– Check the heat exchanger sensor and its connection.
Off – Off – Flashing	Fan Motor Malfunction (indoor)	– Check the fan motor and its connection.
Blink – Blink – Blink	EEPROM error	– Consult a technician to replace or reprogram the EEPROM.
Blink – Blink – Blink	Option Error	– Check option settings and make necessary corrections.
Off – Flashing – Flashing	Abnormal Communication Error (Interior – Exterior)	– Check the connections between the indoor and outdoor unit.
Flashing – Off – Flashing	Outdoor Unit Temperature Sensor Error (Outdoor Temperature Sensor, Defrost Temperature Sensor, OLP Temperature Sensor, Discharge Temperature Sensor, Heat Sink Temperature Sensor)	– Check the outside temperature sensors and their connections.

Regarding the display of the outdoor unit board error mode:

Lights (Yellow-Green-Red)	Description	Possible Causes and Solutions
Off – Off – Off	Off / VDD NG (No Power / VDD Not Good)	– Check if there is power and adjust the power supply.
Off – Off – Flashing	Compressor Peak Current (OC)	– Check compressor power and make necessary repairs.
Off – Off – On	NG Communication (No Communication)	– Check communication connections and correct problems.
Off – Flashing – Off	Compressor Start Error	– Check the compressor starting system and make any necessary repairs.
Off – Flashing – Flashing	Heat Sink Sensor Error	– Check the heat sink sensor and make necessary repairs.
Off – Flashing – On	Normal Operation	– The unit is operating normally.

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Green Thermo King Alarm	Yellow Thermo King Alarm	Red Thermo King Alarm
It is a stored alarm. Indicates a condition that needs investigation but does not affect the unit’s operation. The alarm icon appears for 30 seconds when the unit is turned on and then disappears.	Requires verification. This alarm is a warning to take corrective action before an abnormal condition becomes serious. The alarm icon will appear and remain on.	Shutdown alarm indicating conditions that could damage the unit. The unit will shut down automatically, the alarm icon will appear, and the entire display will flash on and off.

Thermo King Alarms:

This table shows the alarm codes for Thermo King equipment, possible causes of the issue, and some measures to take.

• Thermo King alarms are generated when the microprocessor detects an abnormal condition.
• Multiple Thermo King alarms can occur simultaneously.
• All generated alarms will be stored in memory until the operator clears them.
• Document all alarm cases and communicate them to the service technician.
• The Thermo King alarm table in Spanish shows all codes for all possible applications. Therefore, not all codes will be applicable to each individual unit.
• The operator can repair certain faults, while others can only be repaired by the Thermo King dealer.
• Some alarms may exist with Code 84.
• The alarm may disappear automatically if the condition does not repeat.
• Alarms that occur during a previous trip or a self-check of the unit will be preceded by a hyphen.
• Some alarms are automatically self-eliminated when the operating condition that caused the alarm returns to normal.

Meaning of Thermo King Alarm Codes:

Alarm Code	Equipment Status Identification Color	Operator’s Action
Alarm Code 00	Green = OK No alarms	No action required.
Alarm Code 02	Yellow Check the evaporator temperature sensor (zone)	Check the temperature manually. Report the alarm at the end of the day.
Alarm Code 03	Yellow Check (control) the return air temperature sensor (zone)	Check the temperature manually. Report the alarm at the end of the day.
Alarm Code 04	Yellow Check (control) the discharge air temperature sensor (zone)	Check the temperature manually. Report the alarm at the end of the day.
Alarm Code 05	Green = OK Check the ambient temperature sensor	Report the alarm at the end of the day.
Alarm Code 06	Green = OK Check the engine refrigerant temperature sensor	Report the alarm at the end of the day.
Alarm Code 07	Green = OK Check the engine revolutions or RPM sensor	Report the alarm at the end of the day.
Alarm Code 08	Yellow Unit operating with evaporator sensor (zone)	Check the temperature manually. Report the alarm at the end of the day.
Alarm Code 09	Yellow High evaporator temperature (zone)	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 10	Red Take immediate action High compressor discharge pressure (or temperature)	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 11	Yellow Unit or zone control on alternative sensor (zone)	Monitor the temperature manually. Report the alarm at the end of the day.
Alarm Code 12	Red Take immediate action Sensor or digital input off (zone)	The unit or zone cannot operate and is off. Repair immediately.
Alarm Code 13	Yellow Sensor check (zone)	Check the temperature manually. Report the alarm at the end of the day.
Alarm Code 14	Green = OK Thawing completed by time	Report the alarm at the end of the day.
Alarm Code 15	Yellow Check the glow plugs or the diesel engine air intake heater.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 16	Green = OK Manual start not completed	Report the alarm at the end of the day.
Alarm Code 17	Yellow Engine did not start	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 18	Yellow High temperature of the diesel engine coolant.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 19	Yellow Low oil pressure of the diesel engine.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 20	Yellow Engine (CR steam engine) did not start	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 21	Yellow Cooling cycle check (zone)	Check the temperature manually. Report the alarm at the end of the day.

Table 1: Alarms 31-57

Alarm Code	Status	Description	Action
31	Yellow	Check the oil pressure switch	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
32	Red	Take immediate action	Low cooling capacity (zone)
33	Green = OK	Check diesel engine RPM	Report the alarm at the end of the day.
34	Yellow	Check modulation circuit	Check the temperature manually. Report the alarm at the end of the day.
35	Red	Take immediate action	Check the operating relay circuit
36	Red	Take immediate action	Electric motor did not operate
37	Green = OK	Check diesel engine coolant level	Report the alarm at the end of the day.
38	Red	Take immediate action	Reversed electrical phase
39	Yellow	Check water valve circuit	Check the temperature manually. Report the alarm at the end of the day.
40	Yellow	Check high-speed circuit	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
41	Yellow	Check diesel engine coolant temperature	Report the alarm at the end of the day.
42	Yellow	Unit forced at low speed	Report the alarm at the end of the day.
43	Green = OK	Unit forced at low modulation speed	Report the alarm at the end of the day.
44	Red	Take immediate action	Check the fuel system
45	Yellow	Check hot gas bypass circuit	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
46	Yellow	Check air flow (zone)	Check the temperature manually. Report the alarm at the end of the day.
47	Red	Take immediate action	Remote sensor shutdown
48	Red	Take immediate action	Check belts or clutches associated with the diesel engine.
49	Green = OK	Check spare sensor 1	Report the alarm at the end of the day.
50	Green = OK	Reset the clock	Report the alarm at the end of the day.
51	Red	Take immediate action	Check shutdown circuit
52	Yellow	Check heating circuit (zone)	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
53	Yellow	Check economizer valve circuit	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
54	Green = OK	Test mode wait time	Clear the alarm and restart the unit.
55	Green = OK	Check diesel engine speeds	Operator action: report the alarm at the end of the day.
56	Yellow	Check low-speed evaporator fan (zone)	Operator action: If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
57	Yellow	Check high-speed evaporator fan (zone)	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.

Table 2: Alarms 61-90

Alarm Code	Status	Description	Action
61	Yellow	Low battery voltage	Check with a multimeter. If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
62	Red	Take immediate action	Ammeter out of calibration
63	Red	Take immediate action	Engine or steam engine stopped
64	Green = OK	Pre-trip reminder	Report the alarm at the end of the day.
65	Yellow	Abnormal temperature differential (zone)	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
66	Red	Take immediate action	Low diesel engine oil level
67	Yellow	Check liquid line solenoid circuit	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
68	Red	Take immediate action	Internal controller fault code
70	Green = OK	Hour counter failure	Report the alarm.
71	Green = OK	Hour counter 4 exceeds set time limit	Report the alarm at the end of the day.
72	Green = OK	Hour counter 5 exceeds set time limit	Report the alarm at the end of the day.
73	Green = OK	Hour counter 6 exceeds set time limit	Report the alarm at the end of the day.
74	Green = OK	Controller reset to default values	Report the alarm at the end of the day.
75	Red	Take immediate action	Controller

Table 1:

Alarm Code	Color	Description	Action
61	Yellow	Low battery voltage. Check with a multimeter.	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
62	Red	Take immediate action. Ammeter out of calibration.	The unit cannot operate and is turned off. Repair immediately.
63	Red	Take immediate action. Engine or steam engine stopped.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
64	Green	OK. Pre-trip reminder.	Report the alarm at the end of the day.
65	Yellow	Abnormal temperature differential (zone).	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
66	Red	Take immediate action. Low diesel engine oil level.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
67	Yellow	Check the solenoid circuit of the liquid line in the cooling circuit (zone).	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
68	Red	Take immediate action. Internal controller fault code.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
70	Green	OK. Hour counter failure.	Report the alarm.
71	Green	Hour counter 4 exceeds the set time limit.	Report the alarm at the end of the day.
72	Green	Hour counter 5 exceeds the set time limit.	Report the alarm at the end of the day.
73	Green	Hour counter 6 exceeds the set time limit.	Report the alarm at the end of the day.
74	Green	Reset the controller to default values.	Report the alarm at the end of the day.
75	Red	Take immediate action. Controller RAM error.	Operator action: If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
76	Red	Take immediate action. Controller EPROM failure.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
77	Red	Take immediate action. Controller EPROM checksum error.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
78	Red	Take immediate action. Data register EPROM error.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
79	Green	OK. Internal data register overflow.	Report the alarm at the end of the day.
80	Green	OK. Check the compressor temperature sensor.	Operator action: Report the alarm at the end of the day.
81	Red	Take immediate action. High compressor temperature.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
82	Red	Take immediate action. Shutdown due to high compressor temperature.	The unit cannot operate and is turned off. Repair immediately.
83	Green	OK. Low engine coolant temperature.	Report the alarm at the end of the day.
84	Green	OK. Null reset.	Report the alarm at the end of the day.
85	Green	OK. Forced unit operation.	Operator action: Report the alarm at the end of the day.
86	Green	OK. Check the discharge pressure sensor.	Report the alarm at the end of the day.
87	Green	OK. Check the suction pressure sensor.	Report the alarm at the end of the day.
88	Green	OK. Reserved for CR.
89	Green	OK. Check the electronic expansion valve (ETV) circuit.	Operator action: If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
90	Green	Electrical overload.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.

Table 2:

Alarm Code	Color	Description	Action
91	Green	OK. Check the electrical input.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
92	Green	OK. Sensor degrees not set (zone).	Operator action: Report the alarm at the end of the day.
93	Green	OK. Low compressor suction pressure.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
94	Green	OK. Check charger circuit #1.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
95	Green	OK. Check charger circuit #2.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
96	Yellow	Low fuel level.	Add fuel as needed.
97	Red	Take immediate action. Remote air return sensor failed (CR).	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
98	Green	OK. Check the fuel level sensor.	Report the alarm at the end of the day.
99	Red	Take immediate action. High compressor pressure ratio.	Operator action: If the unit/zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
100	Yellow	Heater fan failure (CR).	If the unit/zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
100	Red	Take immediate action. Evaporator coil outlet temperature control (CR).	Monitor temperature manually. Report the alarm at the end of the day.
102	Yellow	Low evaporator coil temperature (CR).	If the unit/zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
103	Yellow	Low

Alarm Code	Status	Description	Operator Action
91	Green = OK	Check electrical input ready.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
92	Green = OK	Sensor degrees not set (zone).	Operator Action: Report the alarm at the end of the day.
93	Green = OK	Low compressor suction pressure.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
94	Green = OK	Check charger circuit #1.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
95	Green = OK	Check charger circuit #2.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
96	Yellow	Low fuel level.	Add fuel as needed.
97	Red	Immediate action required.	Failed remote air return sensor (CR).
98	Green = OK	Check fuel level sensor.	Report the alarm at the end of the day.
99	Red	Immediate action required.	High compressor pressure ratio.
100	Yellow	Heater fan failure (CR).	If the unit or zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
100	Red	Immediate action required.	Evaporator coil output temperature control (CR).
102	Yellow	Low evaporator coil temperature (CR).	If the unit/zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
103	Yellow	Low heater fuel level (CR).	Monitor temperature manually. Report the alarm at the end of the day.
104	Yellow	Check remote fan speed (zone).	Operator Action: Monitor temperature manually. Report the alarm at the end of the day.
105	Yellow	Check tank receiver sun press circuit.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
106	Yellow	Check purge valve circuit.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
107	Yellow	Check condenser sun input circuit.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
108	Yellow	Door open wait time (zone).	Close doors. Report the alarm at the end of the day.
109	Check high discharge pressure sensor.	Replaced by alarm code 86.
110	Yellow	Check suction line sun circuit (zone).	If the unit/zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
111	Green = OK	Unit not configured correctly (zone).	Operator Action: Report the alarm at the end of the day.
112	Yellow	Check remote fans (zone).	If the unit/zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
113	Yellow	Check electric heating circuit (zone).	Monitor temperature manually. Report the alarm at the end of the day.
114	Red	Immediate action required.	Multiple alarms: cannot run (zone).
115	Yellow	Check high-pressure cutout switch.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
116	Green = OK	Check high-pressure cutout switch.	Operator Action: Report the alarm at the end of the day.
117	Green = OK	Automatic switch from diesel to electric.	Operator Action: Normal operation; does not affect performance.
118	Green = OK	Automatic switch from electric to diesel.	Normal operation; does not affect performance.
119	Reserved for CR.
120	Yellow	Check alternator excitation circuit.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.

Table 2:

Alarm Code	Status	Description	Operator Action
121	Yellow	Check liquid PMW injection circuit.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
122	Yellow	Check electrical or diesel circuit.	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
123	Yellow	Check evaporator coil inlet temperature sensor (CR).	Monitor temperature manually. Report the alarm at the end of the day.
124	Green = OK	Check evaporator coil outlet temperature sensor (CR).	Report the alarm at the end of the day.
125	Yellow	Check tank level sensor (CR).	Operator Action: If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
126	Yellow	Check back pressure regulator (CR).	Monitor temperature manually. Report the alarm at the end of the day.
127	Yellow	Setpoint not entered (zone).	Ensure the setpoint is adjusted to the required temperature.
128	Green = OK	Maintenance reminder #1 engine runtime/service date.	Operator Action: Report the alarm at the end of the day.
129	Green = OK	Maintenance reminder #2 engine runtime.	Report the alarm at the end of the day.
130	Green = OK	Maintenance reminder #1 engine runtime.	Report the alarm at the end of the day.
131	Green = OK	Maintenance reminder #2 electric runtime.	Report the alarm at the end of the day.
132	Green = OK	Maintenance reminder #1 total unit runtime.	Operator Action: Report the alarm at the end of the day.
133	Green = OK	Maintenance reminder #2 total unit runtime.	Report the alarm at the end of the day.
134	Green = OK	Controller runtime hours

Table 1:

Alarm Code	Status	Description
121	Yellow	Check the PMW liquid injection circuit. If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
122	Yellow	Check the electrical or diesel circuit. If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
123	Yellow	Check the evaporator coil (CR) inlet temperature sensor. Monitor the temperature manually. Report the alarm at the end of the day.
124	Green	OK. Check the evaporator coil (CR) outlet temperature sensor. Report the alarm at the end of the day.
125	Yellow	Check the tank level sensor (CR). Operator action: If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
126	Yellow	Check the pressure regulator (CR). Monitor the temperature manually. Report the alarm at the end of the day.
127	Yellow	Point not set (zone). Ensure the setpoint is adjusted to the required temperature.
128	Green	OK. Maintenance reminder #1 for engine runtime/service date. Operator action: Report the alarm at the end of the day.
129	Green	OK. Maintenance reminder #2 for engine runtime. Report the alarm at the end of the day.
130	Green	OK. Maintenance reminder #1 for engine runtime. Report the alarm at the end of the day.
131	Green	OK. Electrical runtime maintenance reminder #2. Report the alarm at the end of the day.
132	Green	OK. Maintenance reminder #1 for total unit runtime. Operator action: Report the alarm at the end of the day.
133	Green	OK. Maintenance reminder #2 for total unit runtime. Report the alarm at the end of the day.
134	Green	OK. Controller operating hours. Operator action: Report the alarm at the end of the day.
135	Green	OK. Check spare digital inputs. Report the alarm at the end of the day.
136	Green	OK. Check spare digital outputs. Report the alarm at the end of the day.
137	Yellow	Check the damper motor engine heater output. If the unit/zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
138	Green	OK. Real-time clock battery failure (DAS). Report the alarm at the end of the day.
139	Green	OK. Abort evacuation mode. Report the alarm at the end of the day.
140	Unused	–

Table 2:

Alarm Code	Status	Description
141	Yellow	Auto Switch Diesel to Electric Disabled. Report the alarm at the end of the day.
142	Yellow	Check the Thermax valve. If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
143	Green	OK. Check the remote drain hose heater output (zone). Report the alarm at the end of the day.
144	Red	Take immediate action. CAN communication lost to expansion module. The unit cannot operate and is off. Repair immediately.
145	Yellow	Lost ON feedback signal from the controller. If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
146	Green	OK. Software version mismatch. Report the alarm at the end of the day.
147	Yellow	Check the multiple temperature fan speed control output (zone). Monitor the temperature manually. Report the alarm at the end of the day.
148	Yellow	Electric to diesel automatic switch disabled. Report the alarm at the end of the day.
149	Yellow	Unidentified alarm. If the unit/zone shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
150	Green	OK. Low-range sensor (DAS and HMI) (zone). Report the alarm at the end of the day.
151	Green	OK. High-range sensor (DAS and HMI) (zone). Report the alarm at the end of the day.
152	Green	OK. Failed DAS sensor (DAS). Report the alarm at the end of the day.
153	Green	OK. Failed DAS sensor (DAS). Report the alarm at the end of the day.
154	Yellow	Low suction pressure switch failure. If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
155	Red	Take immediate action. CAN communication lost to HMI. The unit cannot operate and is off. Repair immediately.
156	Yellow	Check the liquid or suction heat exchanger bypass valve. If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
157	Green	OK. OptiSet Plus profile discrepancy. Report the alarm at the end of the day.
158	Green	OK. Main software loading error. Report the alarm at the end of the day.
159	Green	OK. Check battery status. Report the alarm at the end of the day.
160	Green	OK. CAN communication lost to radio expansion board. Report the alarm at the end of the day.
161	Green	OK. Invalid DAS real-time clock record (DAS). Report the alarm at the end of the day.
163	Yellow	Emission control failure. If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
175	Yellow	Check the electronic expansion valve (CR). If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
176	Yellow	Check the evaporator pressure sensor (CR). If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
177	Yellow	Check the CO2 tank pressure sensor (CR). If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
178	Yellow	Low CO2 fuel level (CR). If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
180	Yellow	Compressor TriPac Alarm. If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.

Table 1:

Alarm Code 151	Status: Green	Sensor out of high range (DAS and HMI) (zone)	Report the alarm at the end of the day.
Alarm Code 152	Status: Green	Failed DAS sensor (DAS)	Report the alarm at the end of the day.
Alarm Code 153	Status: Green	Failed DAS sensor (DAS)	Report the alarm at the end of the day.
Alarm Code 154	Status: Yellow	Low suction pressure switch failure	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 155	Status: Red	Take immediate action	Description: CAN communications lost to HMI
Alarm Code 156	Status: Yellow	Check liquid or suction heat exchanger valve	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 157	Status: Green	OptiSet Plus profile discrepancy	Report the alarm at the end of the day.
Alarm Code 158	Status: Green	Main software loading error	Report the alarm at the end of the day.
Alarm Code 159	Status: Green	Check battery status	Report the alarm at the end of the day.
Alarm Code 160	Status: Green	CAN communications lost to radio expansion board	Report the alarm at the end of the day.
Alarm Code 161	Status: Green	Invalid DAS real-time clock (DAS)	Report the alarm at the end of the day.
Alarm Code 163	Status: Yellow	Emission control failure	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 175	Status: Yellow	Check electronic expansion valve (CR)	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 176	Status: Yellow	Check evaporator pressure sensor (CR)	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 177	Status: Yellow	Check CO2 tank pressure sensor (CR)	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 178	Status: Yellow	Low CO2 fuel level (CR)	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 180	Status: Yellow	Compressor TriPac alarm	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.

Table 2:

Alarm Code 188	Status: Yellow	DAS microprocessor error report	Report the alarm at the end of the day.
Alarm Code 203	Status: Yellow	Check screen return air sensor (zone)	Monitor temperature manually. Report the alarm at the end of the day.
Alarm Code 204	Status: Yellow	Check screen discharge air sensor (zone)	Monitor temperature manually. Report the alarm at the end of the day.
Alarm Code 216	Status: Green	Check DAS digital inputs (DAS)	Report the alarm at the end of the day.
Alarm Code 233	Status: Green	OK to run, REB off, total conservative	Report the alarm at the end of the day.
Alarm Code 234	Status: Green	Check relative humidity sensor circuit	Report the alarm at the end of the day.
Alarm Code 235	Status: Green	High engine coolant temperature review	Report the alarm at the end of the day.
Alarm Code 250	Status: Green	Reset DAS clock	Report the alarm at the end of the day.
Alarm Code 251	Status: Green	Check radio expansion board settings	Report the alarm at the end of the day.
Alarm Code 252	Status: Green	Check automatic fresh air exchange circuit	Report the alarm at the end of the day.
Alarm Code 253	Status: Green	REB with backup battery, alarms disabled	Report the alarm at the end of the day.
Alarm Code 254	Status: Green	Check auxiliary coolant temperature sensor	Report the alarm at the end of the day.
Alarm Code 500	Status: Yellow	Check host evaporator fan low speed	Not implemented
Alarm Code 501	Status: Yellow	Check host evaporator fan high speed	Not implemented
Alarm Code 505	Status: Yellow	Check road condenser fan motor speed circuit	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 506	Status: Yellow	Check curb condenser fan motor speed circuit	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 507	Status: Green	Check digital displacement output circuit (displacement only)	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 508	Status: Green	OK to run, speed request communication error	Report the alarm at the end of the day.
Alarm Code 509	Status: Yellow	ECU failed to enable	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 510	Status: Yellow	ECU run signal failed	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 511	Status: Green	Engine start waiting time exceeded	Report the alarm at the end of the day.
Alarm Code 512	Status: Yellow	Compressor suction high pressure (displacement only)	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.
Alarm Code 513	Status

Thermo King Alarm 71 can be described through the following table:

Alarm 71 Thermo King:

• Indicator: Green = OK
• Description: Hour meter 4 exceeds the established time limit.
• Operator Action: Report the alarm at the end of the day.

Quantifying through the Hour Meter:

Through the hour meter, various parameters can be quantified:

• Total Hours: The total number of hours the unit has been operational, including protection hours.
• Total Time Hours: The total number of hours the unit has operated in both diesel and electric modes.
• Engine Hours: The total number of hours the unit has operated in diesel mode.
• Electric Operating Hours: The total number of hours the unit has operated in electric mode.

Programmable Reminders:

• Programmable Reminder One: User-programmed, represents the number of hours before a total unit runtime maintenance reminder occurs.
• Programmable Reminder Two: User-programmed, represents the number of hours before a total unit runtime maintenance reminder occurs.
• Ignition Controller: Total hours the ignition controller and HMI control panel have been operational.
• Pretrip Reminder: User-programmable, represents the number of hours before a pre-trip reminder occurs.

Hour Meter Alarm:

• Engine Reminder 1: User-programmable, represents the number of hours before an engine runtime maintenance reminder occurs.
• Engine Reminder 2: User-programmable, represents the number of hours before an engine runtime maintenance reminder occurs.
• Electric Reminder 1: User-programmable, represents the number of hours before an electric operating time maintenance reminder occurs.
• Electric Reminder 2: User-programmable, represents the number of hours before an electric operating time maintenance reminder occurs.

Thermo King Alarm 71 provides valuable information about the operational hours of the unit and allows users to set reminders for timely maintenance, ensuring optimal performance.

The Thermo King Alarm 84 in Spanish has the following characteristics:

Alarm Code 84 Thermo King

• Status: Green = OK
• Null Restart
• Report the alarm at the end of the day

Let’s begin by stating that many times, the main code is 17, but the equipment displays code 84 when attempting to restart. Therefore, we must also discuss code 17.

1. Code 17 Generation:
   • Generated if the engine does not reach 40 RPM or goes above and then falls below 40 RPM during the engine start sequence.
   • This alarm is set as a preventive alarm.
2. Shutdown Alarm:
   • Two attempts to start are made, and then the alarm code 17 “Engine Failed to Crank” is set as a shutdown alarm.
3. Alarm Following Code 20/84:
   • A code 17 following a Code 20/84 “Error Starting” will be set as a shutdown alarm.
4. Check RPM:
   • Use an independent tachometer (photo or stroboscopic light) to verify the engine RPM and compare it with the values indicated by the controller.

Code 84 Thermo King in Spanish – What You Should Know First:

• Error 84 is just an alert to report the problem at the end of the day.
• Try to reset the codes once the load has cooled completely, then run it to see if the problems return.
• If they do, you may have a cooling problem. Check that the condenser fan is working, the system is fully charged with refrigerant, and there are no air leaks in the trailer.

The Thermo King Alarm 84:

• It is a temporary abnormal condition resulting from other alarms.
• The unit shuts down for about 15 minutes.
• The unit will restart after about 15 minutes, or after the condition has been reset, and in most cases, other alarms will have been cleared.
• If after 3 attempts, the condition still occurs, the alarm that caused the shutdown will appear on the screen, and the unit will shut down until the alarm is cleared.
• Code 84 is automatically cleared after the last restart attempt.

Solution for Code 84:

• This alarm occurs if the engine fails to start and run when required.
• The error code is generated when the charging current falls below predetermined limits for a period.
• If the AC current signal frequency from the alternator to the microprocessor falls below a predetermined limit.

What to Do with Alarm Code 84:

1. Verify the power contactor.
2. Check the power source.
3. Using a multimeter, check the alternator’s operation.
4. Check the tension of the drive belts.
5. Check the output amperes on the screen if the unit uses the current bypass.

What to Do with Alarm 84 and the Control Panel:

• This alarm is automatically cleared if the original condition does not recur.
• Indicates that the microprocessor is taking corrective action due to the appearance of shutdown alarm codes 9, 10, 17, 18, 19, 20, 23, 24, 35, 40, 41, 42, 44, or 63, and then attempting a restart to keep the unit running.
• Many of these actions include a “waiting period” (to allow the engine to cool, a high-pressure condition).
• If the corrective action is successful, the original alarm code, as well as Alarm Code 84, are automatically cleared.
• If the initial alarm condition persists, and the corrective measures taken by the microprocessor are unsuccessful, the original alarm code remains.

The Thermo King Alarm 89 indicates the status of the Electronic Throttle Valve (ETV) circuit and is presented in the following table:

Alarm Code 89:

• Color Indicator: Green = OK
• Description: Check the Electronic Throttle Valve (ETV) circuit.
• Operator Action: If the unit shuts down, repair it immediately. Otherwise, report the alarm at the end of the day.

Key Information about Thermo King Alarm 89 and ETV:

The ETV is a variable-position valve operated by a stepper motor. Key details include:

• Location: The ETV is positioned in the suction line between the evaporator and the compressor.
• Pressure Transducers: Discharge and suction pressure transducers provide pressure information to the microprocessor control system.
• Control: The microprocessor directly controls the Electronic Throttle Valve.
• Replacement: The ETV replaces both the throttle valve and modulation valve used in other units.
• Circuit Advantages: The ETV circuit extends maintenance intervals and reduces fuel costs, improving temperature control in Thermo King products.

Parts of the Thermo King ETV:

The main components of the Thermo King ETV include:

1. Output
2. Stepper Motor
3. Valve Body
4. Input

The ETV system enhances cooling system control by providing optimal power usage under variable conditions.

Control of ETV Suction Pressure:

The algorithm for controlling suction pressure is crucial for maximizing capacity. The ETV, a variable-position valve, operates with two internal coils. Key points:

• The ETV position can be monitored using the METERS key.
• A position of 0 indicates a fully closed valve, while 800 indicates a fully open valve.
• The microprocessor tests the ETV valve each time the unit starts if required.
• Alarm Code 89 indicates that the refrigeration system pressures did not respond as expected during the test.

What to Do with Thermo King Alarm 89:

When faced with Alarm 89, follow these steps:

1. Locate the ETV circuit in the upper half of the compressor.
2. Check for loose plugs.
3. Clean ground cables, a common cause of system malfunctions.
4. Verify pressure sensor readings against actual system values.
5. Use the METERS key to monitor ETV operation during the ETV test.
6. The ETV test should start with the valve completely closed (position 0) and increase as the valve opens.
7. Suction pressure should decrease when the valve is fully closed and begin to rise as the valve opens.

Additional Notes on Thermo King Alarm 89:

• The microprocessor disregards test results if the cargo box temperature or ambient temperature is below 10F (-12C).
• The ETV valve test can also be performed using the Service Test Mode.
• Use the METERS key to review ETV functionality during the ETV test.

The Thermo King Alarm 20 indicates that the diesel engine powering the CR steam engine did not start when requested by the microprocessor. The manufacturer provides the following description:

Alarm Code 20:

• Color Indicator: Yellow.
• Description: The engine (CR steam engine) did not start.
• Action: If the unit or area shuts down, repair it immediately. Otherwise, report the alarm at the end of the day.

Causes of Alarm 20:

The causes can be divided into two categories:

1. Mechanical Causes (Related to Fuel Supply):
   • Check for mechanical issues related to fuel supply to the diesel engine.
2. Electrical Causes (Related to Ignition and Fuel Supply Control):
   • Check for issues preventing ignition or affecting the control of fuel supply.

Mechanical Issues with Thermo King Alarm 20:

The normal operation of the fuel system is as follows:

• The electric fuel pump (5) creates a vacuum in the supply line in the fuel tank.
• Atmospheric pressure in the tank pushes fuel upward (line 6).
• Fuel reaches the fuel filter and part travels to the mechanical injection pump (9).
• Fuel is distributed according to the engine sequence to the pistons through the injectors (10).

What to Check with Alarm 20:

If you’re experiencing Alarm 20, it’s likely a fuel system issue. Check the fuel solenoid located at the back of the injection pump.

1. Fuel Solenoid Issues:
   • Clear alarms.
   • Stand in front of the unit and touch the side or back of the fuel solenoid.
   • Turn on the unit, keeping a finger on the solenoid. The unit should make a starting sound.
   • If the solenoid makes a sound, it’s energized and functioning correctly.
2. Blocked Fuel System:
   • Inspect the in-line fuel filter located at the inlet hose fitting of the transfer pump.
   • Remove the bolt and washers.
   • Take out the filter from inside the bolt and check for any clogs.
   • Clean the bolt, screen, and fitting.
   • Reinstall the bolt and washers. Replace the screw-on fuel filter if necessary.
3. Air Presence in the Fuel System:
   • Loosen the manual primer on the transfer pump.
   • Ensure the fuel tank has at least three-quarters of fuel; otherwise, add fuel.
   • Locate the vent fitting on top of the tank near the fuel supply and return lines.
   • Pressurize the fuel tank.
   • Bleed air from the fuel lines.
   • Open the purge bolt on top of the injection pump to release air. If needed, continue pressurizing and priming to remove all air.
4. Confirming Fuel Return:
   • Locate the return fuel line.
   • Loosen the hose connection and gently pull the line to check for fuel.
   • Lack of fuel indicates an air issue; constant, steady flow confirms a functioning fuel system.

Electrical Issues with Alarm 20:

The starter motor provides the initial impulse to the diesel engine for the first revolutions. Key components include:

• Starter motor.
• Starter solenoid.
• Pinion coupling.

The starter only works during startup, engaging through the coupling solenoid. Once the diesel engine starts turning on its own, the solenoid separates the coupling pinion, disconnecting the starter from the diesel engine.

What to Check for Electrical Issues:

1. Battery Voltage:
   • Test the battery voltage to ensure it supplies sufficient voltage to the starter motor.
2. Loose Connections:
   • Check for loose connections that may hinder sufficient current flow to the starter motor.
3. Starter Solenoid Operation:
   • Visually check the starter solenoid for proper operation. You can observe the coupling to the diesel engine or listen for the characteristic sound.
4. Diesel Engine Rotation:
   • Ensure the diesel engine rotates enough when using electric start.
5. Starter Motor Engagement:
   • If the starter engages but doesn’t turn, the issue may lie with the starter motor.

The Thermo King Alarm 17 indicates that the diesel engine powering the compressor of the refrigeration system failed to start when requested by the microprocessor. The manufacturer provides the following description:

Alarm Code 17:

• Color Indicator: Yellow
• Description: The engine did not start.
• Action: If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.

Troubleshooting Steps:

1. Check battery voltage; test battery charge to ensure it can retain the charge internally.
2. Inspect the interface circuit board for fuses and relays, especially fuse F3.
3. Use a grounding wristband to prevent internal damage due to static electricity.
4. Place the unit in continuous mode and observe LEDs on the circuit board, particularly LED 25 for the start signal.
5. Verify for a pushed pin in the circuit 8S connector and check for any open or broken wires.
6. If equipped with an electric standby motor, check the electric motor clutch for any issues.
7. Inspect the starter motor’s condition.
8. Check the relay interface circuit board controlling the fuel cutoff solenoid.

Clearing Alarm Code 17:

• This alarm must be cleared manually through the keyboard interface screen.

Other Possible Alarms:

• Alarm 17 may be accompanied by Alarm 84 (Null Restart), but follow the diagnostic procedure for Alarm 17 first.

Programming the Thermoking Microprocessor for Alarm 17 Detection:

• The microprocessor checks the engine RPM through the engine revolution sensor.
• If the engine RPM is below 40, Alarm 17 is activated.
• Additionally, if the engine RPM is above 40 but suddenly drops below 40, Alarm 17 is triggered.

Recognizing Fault 17 in Thermoking:

Fuel System:

• The electric fuel pump creates a vacuum in the fuel tank supply line.
• Atmospheric pressure in the fuel tank pushes fuel upward.
• Fuel reaches the fuel filter and is distributed to the mechanical injection pump and then to injectors.

Fuel Solenoid:

• When the fuel solenoid is energized, fuel is allowed to pass to the injection pump, enabling the final feed to the injectors.
• It serves as a cutoff system for shutting down the system.

Starter Motor:

• The electric starter motor provides the initial impulse to the diesel engine for the first revolutions.
• Components include the starter motor, starter solenoid, and diesel engine coupling pinion.
• The starter engages the diesel engine through the coupling solenoid, rotates the diesel engine, and disengages once the diesel engine is running.

The Thermo King Alarm 18 can be described in the following table:

Alarm 18 Thermo King
	Yellow. High temperature of the diesel engine coolant.
	If the unit shuts down, repair immediately. Otherwise, report the alarm at the end of the day.

The microprocessor utilizes the engine coolant temperature sensor to monitor its temperature. If the coolant temperature rises above an acceptable level, the microprocessor records alarm codes 41 and probably 18. The microprocessor may also shut down the unit.

Fault Code 18 Thermo King:

A high coolant temperature could cause the engine to overheat in a shorter period than usual.

1. Check for low coolant level or leaks.
2. Start by inspecting the Thermo King equipment thermostat.
3. The thermostat may be faulty or covered in dirt; it should be cleaned and checked for recurring errors.
4. Check if the water pump is functioning correctly.
5. Pressure wash the radiator if necessary.
6. A dirty radiator can hinder air circulation, leading to overheating.
7. Verify if the motor oil is at its usual level.
8. Check if the oil has its normal consistency; diesel can mix with engine oil in case of leaks.

How the Engine Cools:

The diesel engine cooling system transfers heat generated by combustion and friction to the environment. The system includes engine coolant, propelled by the water pump, driven by the diesel engine.

Once the engine coolant has traversed all spaces and equalized the engine temperature, the mixture of water and coolant significantly increases in temperature. It is then transported to the engine radiator.

The radiator, typically made of aluminum, consists of channels that aid in cooling the liquid flowing through the ducts. Hot water enters the radiator from one reservoir and must pass to the other reservoir through small panel ducts, transferring heat to cooler surroundings. The air from driving passes through the panel on the exterior of the ducts, collecting heat and lowering its temperature.

1. Support.
2. Fuel injection line.
3. Cylinder head cover.
4. Exhaust manifold.
5. Water pump.
6. Gearbox cover.
7. Crankshaft pulley.
8. Oil sump.
9. Oil level switch.
10. Level rod.
11. Oil filter.
12. Fuel injection pump.
13. Air intake.

What to Do with Alarm 18:

1. Verify if Alarm 18 is a result of genuine overheating or a false reading.
2. Diesel engines are designed to operate in a temperature range between 80°C and 100°C. The cooling system’s function is to maintain the temperature within this range for optimal engine performance.
3. Check the liquid coolant level and eliminate possible leaks.
4. If the equipment’s thermal load (products) is too high, the cooling circuit pressure increases, causing the diesel engine to exert more effort, leading to overheating.
5. To check engine overheating, use a thermometer pointing at the thermostat box, at the temperature switch or sensor location, and verify temperature values.
6. If the temperature is correct, then check the temperature sensor and connections causing the erroneous Alarm 18.
7. If the engine temperature is indeed high, check the water pump and radiator fan belts.
8. Verify if the cooling system operating pressure is excessive (some systems or above 7 psi (48 kPa)).
9. Check the radiator for airflow obstructions or damaged fins.
10. Check temperatures above and below the thermostat; it should be open at 160 to 190 F [71-88 C].
11. Verify thermostat operation by checking for a significant temperature differential indicating a stuck-closed thermostat.
12. Use a thermometer to check temperatures at the radiator inlet and outlet. The differential should be greater than 25 F (14°C).
13. Clean the radiator if the temperature differential between the inlet and outlet is low.
14. Rule out internal hose obstructions as they can collapse, causing a restriction while the engine is running. Hoses can also internally degrade, restricting the flow of diesel engine coolant.

1. Thermostat housing.
2. Gasket.
3. Thermostat 180 F (82 C).
4. Gasket.
5. Water pump.

The Thermo King alarm code 63 indicates that the diesel engine powering the refrigeration equipment’s compressor has stopped and is unable to start. The manufacturer provides the following description:

Alarma 63 Thermo King
Roja	Take immediate action
Motor Diesel stopped	If the unit shuts down, repair immediately; otherwise, report the alarm at the end of the day.

Thermo king Code 63 Causes:

The code 63 is a troublesome code as there can be various reasons behind its occurrence. As a first recommendation, check if the fuel filters run out of fuel when this happens and rule out clogged pipes. In most cases, Alarm 63 Thermo King is generated due to fuel-related issues.

Common Causes of Engine Blockage (Code 63):

1. Heat: Excessive heat in the exhaust system, engine, or ambient temperature can vaporize fuel in the lines, causing the engine to stop. The most effective way to address this issue is to let the engine cool. Find shade, park your vehicle, and let the engine rest for a few minutes.

What to do with Code 63 on the Control Panel:

1. Download and inspect the ServiceWatch data log information.
2. Review the data using technical user level to determine operating conditions when Code 63 was set.
3. Use the service test mode in operation to replicate operating conditions as needed.
4. Operating data can be viewed in technical mode.
5. Perform a pre-trip test to determine the cause of the shutdown.
6. Check for other alarm codes and proceed as indicated for each code.

How to Physically Address Code 63:

1. Check the fuel level and verify the proper operation of the fuel pump.
2. Inspect the air filter and intake hose for obstructions.

Electrical Checks to Overcome Code 63:

1. Verify unit fuses.
2. Check if the RPM sensor is functioning correctly.
3. Review operation relay and fuel solenoid components and circuits.
4. Check for low battery voltage.
5. Ensure all ground connections on the master ground plate are secure.
6. Check for a seized compressor or motor.

Fuel Solenoid and Code 63:

When the fuel solenoid is energized, it allows fuel to flow to the injection pump, providing the final feed to the injectors. This system acts as a cutoff system to allow system shutdown.

Thermo King Fuel Solenoid

• Check for power at the fuel cutoff solenoid with the ignition on and the engine cranking. If there’s no power, ensure to test all fuses and relays.
• Inspect the wiring of the fuel cutoff solenoid for damage.

Typical Values for Fuel Solenoid:

Solenoide de Combustible a 12.5 voltios corriente continua.	Valores tipicos de resistencia	Valores tipicos de amperaje
Bobina de Puesta en Trabajo	35 a 45	0.2 a 0.3
Bobina de Mantenimiento	0.5	24 a 29

Electrical Verification for Overcoming Code 63:

1. Verify unit fuses.
2. Check if the RPM sensor is functioning correctly.
3. Review operation relay and fuel solenoid components and circuits.
4. Check for low battery voltage.
5. Ensure all ground connections on the master ground plate are secure.
6. Check for a seized compressor or motor.

Failure and Alarm 63 Thermo King:

The starter motor is responsible for giving the initial impulse to the diesel engine so that it can develop its first revolutions.

Components of the Starter Motor:

1. Pinion Gear
2. Starter Motor
3. Plunger
4. Starter Solenoid
5. Pinion Assembly
6. Ring Gear

Starter Motor Operation:

• When energized, the starter motor couples to the diesel engine through the engagement solenoid.
• For the starter motor to begin turning, it must be engaged.
• If the starter solenoid is correct, engagement occurs, and the starter motor turns the diesel to start.

This coupling involves joining (meshing) the pinion assembly (5) to the ring gear (6). Once the diesel engine starts turning on its own, the solenoid disengages the coupling, disconnecting the starter motor.

Starter Motor – Thermo King

These steps should help you troubleshoot and address Thermo King Alarm Code 63 effectively. Always refer to the manufacturer’s documentation for specific details and instructions related to your equipment.

The Thermo King alarm code 14 indicates that the unit has exceeded the defrost time during the defrost cycle.

The defrost cycle is a process that melts the ice and frost that accumulates on the evaporator coil. This ice and frost can block airflow, reducing the unit’s efficiency.

The alarm 14 Thermo King can be described in the following table:

Alarma 14 Thermo king
Verde = OK	Defrosting completed on time
	Report the alarm at the end of the day.

Why does Thermo King code 14 occur?

This error typically occurs when the defrost time is excessively prolonged. In many Thermoking units, electric defrost has a time limit of 90 minutes with a power supply voltage higher than 440 VAC and 120 minutes below 440 VAC.

The electric heating signal is on for too long when:

• There is low voltage from the power source.
• Defective heating elements.
• Evaporator fans are operating during defrost.
• Evaporator sensor is incorrectly placed.
• Evaporator compartment temperature is very low, even under normal operating conditions.

What to do with code 14:

1. Initiate a manual defrost and check the amperage flow and evaporator coil temperature.
2. Evaluate the defrost performance.
3. Open the evaporator door and verify the location of the evaporator coil sensor.
4. It’s crucial to address the underlying issues causing the extended defrost time to ensure proper functionality and prevent further occurrences of alarm code 14